Modern mail room operations are arranged to process mass distribution mailings that may involve the mailing of many individual mail items, each containing one, two, three or more pages. The operation typically includes machines and devices to feed, fold, transport and insert pages into envelopes for eventual mailing. A rotary paper feeding device comprises a rotating cylindrical drum arranged to grip a number of pages for each mail item, for delivery to, for example a folding machine. In connection with the operation of the paper feeding device, it is desirable to measure the thickness of each item gripped by the device, to make certain that the proper number of pages is being delivered to the folding machine.
To that end, various mechanical devices have been provided on the rotating cylinder to press the gripped paper toward the cylinder drum to sense the thickness and thereby determine the number of pages being gripped by the rotating cylinder. The accuracy of the measurement is dependent upon mechanical action of a number of interconnected mechanical devices.
Another prior proposal for determining the number of pages gripped by the rotating cylinder comprises a sensing device in the rotating cylindrical drum to sense the thickness of the gripped pages. The sensing device then transfers the sensed data to a fixed receiving device mounted adjacent to the rotating cylinder. This arrangement requires the use of complex sensing equipment, and also involves an angular delay between sensing the thickness, and the transfer of the data to the fixed receiving device.
Thus, the known mechanisms for sensing the number of pages being feed to a device such as a folding machine have deficiencies that would be advantageous to overcome.